Ralston, I. and Close-Brooks, J. (1987) “The Arbroath Antiquary Club’s excavations at Castle Rock promontory fort, Auchmithie, Arbroath and Saint Vigeans, Angus District”, Proceedings of the Society of Antiquaries of Scotland, 116, pp. 101–115. doi: 10.9750/PSAS.116.101.115.